There is little doubt that the future of the hemlock in North America is uncertain. An exotic pest, the hemlock woolly adelgid, is destroying hemlocks, both eastern, Tsuga Canadensis, and Carolina, Tsuga caroliniana. The adelgid already occurs in 50 percent of the hemlock’s eastern range and is still spreading.

An army of researchers, botanists, conservation and environmental organizations and state and federal agencies has mobilized in North Carolina and across the hemlock’s range to try and save the embattled giant. This long-lived (400 plus years), slow-growing, shade tolerant tree is an ecologically important climax species of eastern forests.

Property owners who utilize hemlocks as ornamentals will be faced with ongoing, expensive pesticide applications if they want to save their trees. The fate of hemlocks in the wild will apparently be decided by the success — or lack of success — of efforts to establish a biological control. A couple of species of exotic beetles are being tested. The efficacy of these efforts is yet to be determined. Even if the predator program works, many hemlock forests in the northeast and in Shenandoah National Park have already been decimated and more will probably be lost.

What is an appropriate human response to this hemlock disaster? You see, North America has lost its hemlock forests before. I consider myself a somewhat informed conservationist but I remember the first time I heard that hemlocks had disappeared at least one time before.

I was leading the Balsam Mountain Preserve section of the Carolina Field Birders’ third annual Christmas Bird Count. We were noting the considerable infestation of adelgids on the preserve when one of the participants, retired Western Carolina University botany professor Dan Pitillio, mentioned that fossil pollen records had documented the demise of the eastern hemlock a few thousand years ago.

Well, that day was dedicated to birds, so I made a mental note of Dan’s statement and kept searching for feathered winter residents. But the hemlock mystery kept pricking my consciousness and a couple of days ago I did an Internet search. I found numerous articles and references to that past decline of the hemlock in eastern North America.

Fossil pollen records gathered from lakebeds and bogs throughout the range of the eastern hemlock all appear to corroborate a dramatic synchronous disappearance of hemlocks sometime between 5,700 and 5,000 years ago. In some studies, hemlock pollen totals declined from 30 percent of all pollens present to less than 5 percent during that time frame. It took between 1,000 and 2,000 years for the hemlock to make a comeback, and in many areas it was never as prominent as before the decline.

A couple of causes were posited for this dramatic loss of hemlocks. One has a familiar ring – insect infestation. The culprit of the past was not an exotic pest, but rather the native hemlock looper. Other studies blame a prolonged drought for the hemlock demise. Most researchers agree that it was probably some combination of the two.

Whatever the reason, hemlocks disappeared and the landscape, environment and ecology changed dramatically. Birches, beeches, pines, maples and oaks increased in the canopy after the decline of the hemlock. Then, after 1,000 years or so hemlocks began to reclaim their dominance in suitable habitat and the environment and ecology changed once again.

And that brings us back to our question — what is an appropriate response to this hemlock disaster? Trust me, I don’t have the answer, but I think it’s the right question to ask. Today’s dilemma certainly has different circumstances from the one 5,000 years ago. It is a product of an introduced exotic pest. What happened in history was a product of natural forces.

I must admit I don’t have much of a problem with natural forces. A forester-friend of mine calls my conception of landscape dynamics, benign neglect. I guess if he means let nature run its course, I’m guilty.

On the other hand, I’m engaged in mortal combat with invasive, introduced bittersweet on my property and would destroy every sprig if I could. But then perhaps I contribute to an unnatural balance by feeding birds in my backyard.

The Holocene, the period from roughly 11,000 years ago to the present, is often referred to as the “Age of Man.” Probably no other creature in the history of our planet has had or will have such an overwhelming impact on its environment and its ecology.

If we packed up our beetles and went home, the hemlock would surely disappear. But if we didn’t gobble up the remaining wilderness and we don’t pollute the water, soil and air beyond repair, I’m betting that within a couple thousand years the hemlock would be back.

The problem is not our response to the hemlock woolly adelgid. The problem is our attitude — the idea that we can fix whatever we break. We are like frogs in a pot of water where the heat is being turned up in unnoticeable, small increments. We adjust and become comfortable never suspecting we’re being boiled alive – somebody needs to yell JUMP!

(Don Hendershot cat be reached at ddihen@juno.com)